Valve seat puller



April 7, 1936. B. F. STOWELL VALVE SEAT FULLER I Filed Sept. 12, 1934 L 7 i u m z T S S R n R N 0 2 m M w w m m m -5 Patented Apr. 7, 1936 i liTED STATES VALVE SEAT PULLER Byron F. Stowell, Springfield, Mass, assignor to Van Norman Machine Tool Company, Springfield, Mass, a corporation of Massachusetts Application September 12,1934, Serial No. 743,648

4 Claims.

It has become customary to provide hardened steel rings as valve seat inserts surrounding the valve ports of internal combustion motors, either as original equipment or as a means of recondi- 5 tioning the valve seats when they have become worn. These rings are so hard that they cannot be effectively recut or refaced and up to the present time no adequate means have been available for removing them from the engine block. It is 39 the object of the present invention to provide a simple and effective mechanism for removing these hardened ring inserts rapidly and without injury to the engine block casting. Additional objects will appear from the following description and claims.

Referring to the drawing:

Fig. l is a top plan View of a portion of the insert removing tool;

Fig. 2 is a side elevation thereof;

Fig. 3 is a section on line 33 of Fig. 1;

Fig. 4 is a section on line 44 of Fig. 2; and

Fig. 5 is a section similar to Fig. 3 but showing the apparatus ready to begin the pulling of the valve seat from the engine block.

The device comprises a body or supporting member Hi having an upwardly extending threaded shank l I. In a recess formed in the bottom of the body portion a pilot I2 is secured in any suitable way, for example by a set screw l3. This pilot can be removed and replaced by another of different size to fit the valve stem guide M of the engine block casting l5 upon which it is to be used. The hardened steel insert ring is shown at l6 in Fig. 5. The sides of the body I0 are flattened off at ll and are tapered so that these sides converge toward the upper portion of the tool. In the form shown in the drawing, three of these flattened portions are shown.

On keys l8 secured to each of the flattened sides 40 I! are mounted wedge shaped cutter bearing members or slides [9. In order to hold these slides assembled upon the body l0 and to give them a tendency to contract, they are provided with a pair of grooves 20 in which lie coiled springs 2|. Each of the slides I9 is formed with cutting ribs 22 suitably formed so that When the device is rotated they will cut a groove in the walls of a hole into which the device is introduced.

Loosely fitting upon the shank II is a cap or bearing member 23 having its periphery flattened as best shown in Fig. 2 to permit the application of a wrench. This cap has projections 24 fitting into slots 25 in the slides [9 so that when the cap is rotated the slides, and therefore the body II], will be rotated with it. Above the cap 23 and threaded onto the shank H is a nut 26 which, when it is screwed downwardly, forces the cap 23 against the slides and therefore pushes them outwardly along the slanting surfaces II.

In the use of the portion of the device which has been described up to this point, the pilot I2 is inserted into the valve guide [4 and the cutting edges 22 are brought to a point just below the ring it. To facilitate the exact positioning of these ribs a stop 21 is mounted upon the cap 23 by a slot and screw connection 28, 29. The distance between the bottom of the stop and the adjacent cutting edge 22 can be predetermined accurately as by slipping a sample ring between them and the stop is then looked in adjusted position. When the device is inserted into the valve port the stop 21 rests upon the top of the insert it, as is clearly shown in Fig. 5, and the cutting ribs 22 will thus be located just below the bottom of the insert. By turning the nut 26 the body In can be drawn up out of the slides l9 forcing them outwardly until the ribs engage the metal below the ring. By rotating the device through the cap 23, together with periodical expansion of the cutting ribs by means of the nut 26, a groove can be cut in the metal below insert [6 to the full depth of the cutting ribs. By exerting an upward pull on these cutting ribs, the ring can now be withdrawn from the engine block.

In order to exert this upward pull on the device, a hood-like member 30 is arranged to be slipped over the shank l l. The top of this hood is preferably spherical and a washer 3| with a spherical lower surface is placed on top of it. Bearing against washer 3| is a nut 32 threaded onto the shank II. This construction permits the use of the device in cases Where the valve stem guide is set at an angle, and could be replaced by a plain washer bearing against the fiat top of the hood in cases where this added adjustability is not required. By tightening up the nut 32 the shank I I will be drawn upwardly. It will be seen from Fig. 5 that this upward pull on the body member It] will force the ribs 22 even more firmly underneath the ring Hi. It has been found in practice that valve ring inserts, even though very tightly held in the casting l5 and even though the metal of the casting has been spun over on the topof the insert, could be removed with great readiness and without any injury to the casting. The slight groove out by the ribs 22 underneath the ring are not in the least detrimental to the subsequent use of the engine block. After the removal of the ring, the shouldered recess in which it lay can be rebored if necessary and a fresh ring can be inserted.

In some cases the ring I 6 or the engine block itself may be preformed with a groove to facilitate removaEo-f the fing. The cutting ribs 22 in these cases will enter'the preformed groove wfihout cutting, but will exert a lifting force on the ringin the manner described above? It will be noted that since the ring withdrawifng and the rib expanding forces are *bbtained' from the slanting surfaces ll, the expanding force which holds the ribs under'jthe ring will be proportional to the withdrawing force, insuring that no matter how tightly the ring may stick the ribs will be held under it with an adequate force.

What I claim is: V

12 A device for withdrawing valve seat insert rings from engine blocks, comprisirjig a supporting member engageable with the valve stem guide of the engine block to be centralized thereby, a series of cutting rrgembers inounted on the supporting member for rotation therewith, means for expanding the cutting members whereby they will out a groove in the engine block underneath the rings as the supporting member is rotated, and means for exerting a pulling force between the cutting members and the facegof the engine block. r i

2. A device for withdrawing valve seat insert rings from engine blocks, comprising a supporting member having a pilot engageable with the valve stem guide (if the engine block to be centralized thereby, said supporting member having slanting bearing surfaces converging in an upward direction, a plurality of cutting members mounted on said bearing surfaces so as to be coupled to the supporting member for rotation therewith and to be free for sliding movement thereon to expand the cutting members, means for causing relatige sliding movement of the cutting members on the supporting member whereby they may be expanded to cut a groove in the engine block underneath the rings as the supporting member is rotated, and means for; exerting a pulling force between the cutting members and the face of the engine block. a

3. A device for withdrawing valve seat insert rings from engine blocks, comprising a supporting member having a pilot engageable with a Valve stem guide of the engine block to be centralized thereby, said supporting member having slanting bearing surfaces converging in an up- Ward direction and having a threaded upwardly projecting shank, a plurality of wedge-shaped members 'siidably mounted on said bearing surfaces and coupled to the supporting member for rotation therewith, cutters on said wedge-shaped members, *spring means tendingf to hold said wedge-shaped members in contrac'ted position, a bearing member fitting on the threaded shank and engaging thejwedge-shaped members, a nut on the shank whereby the shank may be drawn upwardlyfrelatively to the bearing member and the wedge-shaped members, and the wedgeshaped members thus expanded, means vtfjhereby the supporting member can be rotated, a hood member fitting over the threadedfshank and engageable with the face of the engine block, and 7 means having threaded; engagement with the shank and engageable with the hood member for raising the suppprting member and thecutters members slidably mounted on said bearing surfaces and coupled to the supporting member for; rotation; therewith, cutters on said Wedge-shaped members, spring means tending to h old said wedge-shaped members in contracted iposition a bearing member fitting on the threaded shank and engaging the Wedg e-shaped members, a nut on theishank whereby the shank may be drawn upwardly relatively to the bearing member and the wedge-sh@ed members, and the wedgeshaped members thus expanded, means whereby the supporting member can be rotated, a stop carried by the bearing member and engageable with the face of the engine block to determine the distance below said face at which the cutters are located, a hood member fitting over the threaded shank and engageable with the face of the engine block, and means having threaded engagement with the shank and engageable with the hood member for raising the supporting member and the cutter relative to the engine block.

BYRON F. STOWELL. 

